Terminals 1 - 6 – tekmar 274 Boiler Control User Manual
Page 21
21 of 44
© 2012 274_D - 11/12
Boiler Demand
To generate a Boiler Demand, a voltage between 20 V (ac)
and 260 V (ac) must be applied across the Boiler Demand
terminals (21 and 22).
DHW
Demand
To generate a DHW Demand, a voltage between 20 V (ac)
and 260 V (ac) must be applied across the DHW/Setp and
Com Dem terminals (23 and 24). The Pump Sequencer
DIP Switch must be set to Off and DHW MODE must be
set to 1 through 5.
Setpoint Demand
To generate a Setpoint Demand, a voltage between 20 V
(ac) and 260 V (ac) must be applied across the DHW/Setp
and Com Dem terminals (23 and 24). The DHW MODE
must be set to OFF.
Proof Demand
To generate a Proof Demand, a voltage between 20 V (ac)
and 260 V (ac) must be applied across the Pr. Dem and
Com Dem terminals (25 and 24).
Energy Management System (EMS)
To generate an external input signal from an Energy
Management System (EMS), either a 0 to 10 V (dc) or 2
to 10 V (dc) signal must be applied to the Com – and Out
+ terminals (2 and 3).
A 0 - 20 mA signal can be converted to a 0 - 10 V (dc) signal
by installing a 500 Ω resistor in parallel between the Com
– and Out + terminals (2 and 3).
A 4 - 20 mA signal can be converted to a 2 - 10 V (dc) signal
by installing a 500 Ω resistor in parallel between the Com
– and Out + terminals (2 and 3).
Note: DIP Switch must be set to EMS.
Dem
Dem
/Setp
Pr.
Com
DHW
25
24
23
20 to 260
V (ac)
L
N
Demand
Boiler
22
21
20 to 260
V (ac)
L
N
Dem
Dem
/Setp
Pr.
Com
DHW
25
24
23
20 to 260
V (ac)
L
N
Dem
Dem
/Setp
Pr.
Com
DHW
25
24
23
20 to 260
V (ac)
L
N
+
-
Out
Com
3
2
0-10 V (dc)
or
2-10 V (dc)
+
-
OR
+
-
Out
Com
3
2
0 - 20 mA
or
4 - 20 mA
+
-
500
Ω
Resistor
Non-Powered Input Connections
Terminals 1 - 6
tN4
Terminals 1 and 2 provide a tN4 connection for tN4 devices
on the tN4 bus. Connect terminals 1 (tN4) and 2 (Com) to
the corresponding terminals on the tN4 devices that are
to be connected.
Note: The connection is polarity sensitive. Ensure that
terminal 1 (tN4) is connected to the tN4 terminal on the tN4
device and that terminal 2 (C) is connect to the C terminal
on the tN4 device.
-
Com
tN4
2
1
tN4
Device
Com
tN4